Re: [ima-evm-utils PATCH 07/12] Update ima_measurements to define and use a local list of public keys

[Stefan Berger]

On 11/19/23 11:50, Mimi Zohar wrote:
Replace calling init_public_keys() with the init_public_keys2() version.
Similarly replace ima_verify_signature() with the ima_verify_signature2()
version.

Update the static ima_ng_show() function definition to include a
"public_keys" parameter.

Free the local public keys list.

Signed-off-by: Mimi Zohar <zo...@linux.ibm.com>
---
  src/evmctl.c | 18 +++++++++++-------
  1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/src/evmctl.c b/src/evmctl.c
index f796edfce5f1..ad4565b3ee52 100644
--- a/src/evmctl.c
+++ b/src/evmctl.c
@@ -1614,7 +1614,7 @@ static int lookup_template_name_entry(char *template_name)
        return 0;
  }
  
-void ima_ng_show(struct template_entry *entry)
+static void ima_ng_show(void *public_keys, struct template_entry *entry)
  {
        uint8_t *fieldp = entry->template;
        uint32_t field_len;
@@ -1740,10 +1740,12 @@ void ima_ng_show(struct template_entry *entry)
                 * the measurement list or calculate the hash.
                 */
                if (verify_list_sig)
-                       err = ima_verify_signature(path, sig, sig_len,
-                                                  digest, digest_len);
+                       err = ima_verify_signature2(public_keys, path,
+                                                   sig, sig_len,
+                                                   digest, digest_len);
                else
-                       err = ima_verify_signature(path, sig, sig_len, NULL, 0);
+                       err = ima_verify_signature2(public_keys, path,
+                                                   sig, sig_len, NULL, 0);
  
  		if (!err && imaevm_params.verbose > LOG_INFO)
                        log_info("%s: verification is OK\n", path);
@@ -2223,6 +2225,7 @@ static int ima_measurement(const char *file)
        int first_record = 1;
        unsigned int pseudo_padded_banks_mask, pseudo_banks_mask;
        unsigned long entry_num = 0;
+       void *public_keys = NULL;
        int c;
  
  	struct template_entry entry = { .template = NULL };
@@ -2252,9 +2255,9 @@ static int ima_measurement(const char *file)
        }
  
  	if (imaevm_params.keyfile)	/* Support multiple public keys */
-               init_public_keys(imaevm_params.keyfile);
+               init_public_keys2(imaevm_params.keyfile, &public_keys);
        else                            /* assume read pubkey from x509 cert */
-               init_public_keys("/etc/keys/x509_evm.der");
+               init_public_keys2("/etc/keys/x509_evm.der", &public_keys);
        if (errno)

Hm, a failing malloc() sets errno, so this would be ok. I would change 
this to check for return value != 0 from init_public_keys2().

                log_errno_reset(LOG_DEBUG,
                                "Failure in initializing public keys");
@@ -2405,7 +2408,7 @@ static int ima_measurement(const char *file)
                if (is_ima_template)
                        ima_show(&entry);
                else
-                       ima_ng_show(&entry);
+                       ima_ng_show(public_keys, &entry);
  
  		if (!tpmbanks)
                        continue;
@@ -2464,6 +2467,7 @@ out_free:
        free(pseudo_banks);
        free(pseudo_padded_banks);
        free(entry.template);
+       free_public_keys(public_keys);
  
  	return err;
  }